18x9.5 40mm offset on the front

[Pro Stock John]

Cool good to know. Ordered 5mm, we'll see.

[Pro Stock John]

Posted to me in a different thread:

Originally Posted by ihada69L78

PSJ,[ATTACH][/ATTACH]

Thought I'd let you know what I found out about using 18X9.5 Vette wheels on the front.
I'm running square 295-45-18's on Grand Sport wheels. The section width is 11 3/16. I had the same problem with no strut clearance and went with AKATA 5mm spacers. I found two issues. The AKATA spacers I got last fall are 5 7/8" diameter and the wheel mounting pad is 6". Might not be a problem but I thought I'd make you aware of it. Biggest issue is that when you use a 5mm spacer you only have 4 and 3/4 threads of the lug nut on the stud. (DOT requires 6 threads on new manufactured products.) I used Gorilla 68148 ET lug nuts to get enough threads on the stud. Again, might not be a problem????
I've got some 3mm spacers ordered in hopes I can use the factory nuts since I think they are stronger than using ET nuts. I'm sure it would not be an issue if you only go fast in a straight line. In addition to the drag strip, I go to the road course occasionally.
Hope this helps.

IHADA69l78. Gary

[ihada69L78]

PSJ

Did you measure the section width of your tires yet?
The GM part # for 7mm longer wheel studs is 11588810, but the ET lug nuts is easier. Look at them and you'll see what I mean.
My 3mm spacers are supposed to ship today so maybe i'll know if they will work with the stock lugs by this weekend. 3mm spacers should be 1/8" clearance with an 11 3/16 section width tire.

[Pro Stock John]

10.433070866141733?

Typed in tire size here, not sure if I did it right?

[Pro Stock John]

And I'm using lugs like this, what do you think?

[Jason@JacFab]

Not sure if you saw in the Free wheel offsets thread, but SUX2BU corrected me on the "toe"... It was actually the CAMBER that I changed to get the tires to clear the strut...

[Pro Stock John]

I saw that, but I'm not sure what to do with the information.

[ihada69L78]

Wheel width affects tire sidewall overall width. Lay your tire/wheel, inflated to proper pressure, on the floor, lay a straight edge from sidewall to sidewall, and measure from the floor to the straight edge.
Google gorilla 68148 to see what ET lug nuts are.

[Pro Stock John]

Hey Gary, just did a quick measurement with a ruler looks like 11 & 1/4 inches, right around there. but that doesn't seem right to me as the wheel is 9.5 inches wide and the tire is not much wider... lol.

I'm going to put a long piece of painters tape on the strut before I re-mount the wheels, and then I'll drive around and see if they rub.

So you are getting those 3mm spacers from that place, they are $70 right.. 3mm might work for me too, so if they don't work out let me know. My 5mm's show up tomorrow so if I can I'll change 'em over after I get home from work.

[Nine Ball]

All this work because of cheap wheels that don't fit. Changing studs, grinding suspension, using spacers.... ugh.

These Camaros are heavy beasts. I'd not recommend any spacers or fewer stud threads.

The other bad thing about spacers is that most of them make you lose the hub centric feature of a wheel. This puts more shear stress on the studs.

[ihada69L78]

"All this work because of cheap wheels that don't fit. Changing studs, grinding suspension, using spacers.... ugh."


I'm not sure i would characterize my factory GM wheels as "cheap" but I do agree with your concerns.
I went with Grand Sport (did I mention these are factory GM wheels), not because they are cheap but because I think chrome or polished wheels look good on a white car and I was too cheap (there's that word again) to pay twice as much for the only wheels I thought looked as good as the Grand Sport wheels. I also was under the impression the GS wheels would fit without spacers, but I discovered after I bought and mounted them that they wouldn't. I didn't have any choice but to use small spacers and I did address the lug nut thread issue.

[Jason@JacFab]

With a spacer as small as 3mm, I would think that you still would keep the "hub centric" feature. I want to say the "hub nub" sticks out a good .25 to .3125"... I'd have to measure...

I kept the GS wheels off of my SS before I got rid of it and got this 13 LFX car, and I've been wanting to put them back on, but didn't really want to grind the spindle, or mess with the camber again...

This thread as brought the spacer idea back to my attention, and after looking at the spacers on ebay, I thought to myself, "Hey, I have a waterjet machine at my disposal, why can't I just cut some spacers out of .125" material?" .125" = ~3.175 MM... Pretty sure the hub nub will still stick out and go into the wheel bore even with the spacer.

$70 for the 3mm? If all they are is just a flat plate with some holes, and don't have a hub nub on them (like the ebay ones look to be.), I can make them way cheaper than that! I think I'll make myself a set and try them w/ the GS wheels on my car!

I bought the GS wheels because they were cheap, the were 18s that fit the SS brakes (w/ a little modification), and they look good. I can't justify spending a butt load of money on wheels personally... But that's just me.

[ihada69L78]

PSJ,
My section width is the same as yours so you should have about 3/16" clearance with 5mm spacers. You can check the clearance by turning the wheels and using allen wrenches to measure. I'll let you know as soon as my 3mm spacers get here how much clearance, should be 1/8", and if they will work with regular lug nuts.
And the hub centric/wheel centric spacers are $70.00.

[Nine Ball]

For those of you running 10mm spacers, you can always get Extended Thread (ET) lug nuts to get back some of that thread engagement. These have a 0.33" thread extension, which is equal to 8.3mm of thread. So, you'd only lose 1.7mm of thread total when using a 10mm spacer. Camaro uses 14mm x 1.5 lug thread.

http://www.fastwheelaccessories.com/...1-5-chrome-et/

Or, buy wheels that fit properly.